Electrical cable connector part



Oct. l, 1968 K. FISCHER ELECTRICAL CABLE CONNECTOR PART Filed Oct. l2, 1966 77% ws@ NN United States Patent O 3,404,363 ELECTRECAL CABLE CONNECTOR PART Kurt Fischer, iufftcn, Ind., assignor to Franklin Electric Co., Inc., Bluffton, 1nd., a corporation of indiana Filed Oct. 12, 1966, Ser. No. 586,227 6 Claims. (Cl. 339-60) This invention relates to electrical wiring connections, land more particularly to an improved plug part of a sealed cable connector adapted to lbe submersed in a high pressure electrically conductive liquid.

lt is an object of this -invention to provide a plug part of a sealed electrical connector having socket part adapted to mate with the plug part, including a novel and inexpensive connector clamp.

Still another object is to provide a plug part of the foregoing character, including improved orienting means.

A still further object is to provide a plug part of the foregoing character, which effectively seals the plug part against entry of liquid.

Other objects and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying figures of the drawing, in which:

FIG. 1 is a perspective view of an electrical cable connector embodying the features of the invention;

FIG. 2 is an enlarged longitudinal sectional view showing the parts of the cable connector when separated but in position to be assembled to each other;

FIG. 3 is a sectional view taken on the line 3 3 of FG. 2;

FG. 4 is a sectional View taken on the line 4-4 of FIG. 3;

FIG. 5 is a longitudinal sectional view of the connector with the parts secured to each other; and

FIG. 6 is an enlarged sectional view of a part of the connector.

In general, an electrical connector incorporating the invention is designed to be submersed in a high pressure fluid, and comprises plug and socket parts designed to =be connected together. Electrical wire conductors are secured to each of the parts and, when the parts are connected together, sealed electrical connections are made between the wires of the two parts. Since it is important that each wire of one part be electrically connected to a L certain wire of the other part, improved orienting means are provided to ensure proper connection of the parts.

When the connector and the wires attached thereto are submersed in a high pressure electrically conductive liquid, it is possible that the liquid may enter a break, for example, in the insulation surrounding one of the wires at a location displaced from the connector and creep between the strands making up the wire to the connector. To prevent the liquid from entering the connector and short circuiting the wires Within the connector, a novel Iand r improved water block clamp is provided at the ends of the wires secured to the plug part of the connector. In addition, the construction of the plug part is improved to provide added protection against liquid creepage around the water block clamps.

In greater detail, an electrical connector 1t) incorporating the invention is designed to connect the wires 11, 12 and 13 `of a cable 14 to three wires 16, 17 and 18. The electrical connector 1t) comprises a plug portion 21 and a socket portion 22 which are designed to be connected together by a nut threaded into the socket part 22 and bearing longitudinally against the plug part 21. When so connected, the plug and socket parts electrically connect the wires 11, 12 `and 13 to the wires 16, 17 and 18, respectively and to form a liquid tight seal around the wires.

The socket part 22 of the electrical connector 10 com- 3,404,363 Patented ct. 1, 1968 prises a metal sleeve 23 (FIG. 2) and an insulating body 24. The insulating body 24 extends into the interior of the sleeve 23 at one end thereof and has its end surface, indicated at 26, spaced from the other end of the sleeve to provide a socket portion 27 within'the sleeve 23. The conductors 16, 17 and 18 extend into and are embedded in the insulating body 24, the ends of the wires 16, 17 and 18 being arranged in triangular relation with each other at their inner ends, and prongs 28 are electrically connected to the ends of the wires 16, 17 and 18, the prongs 28 also being embedded in the insulating body 24 but projecting beyond the end thereof. The insulating body 24 and the adjacent portion of the sleeve 23 may be cased in an insulating sleeve 29, 0r threads may be formed on the outer periphery of the sleeve 23 for connection of the sleeve 23 to an end bell of a motor, for example.

The prongs 28 are also arranged in triangular relation and project beyond the end surface 26 of the insulating body 24 and into the socket portion 27 of the sleeve 23. Beyond the socket portion 27, the sleeve 23 is provided with an enlarged portion 31 providing an inner transverse shoulder 32 at the outer end of the socket portion 27. The interior of the enlarged portion 31 for at least a portion of its length is threaded as -at 33, and a longitudinally extending groove 34 is provided at one side of the enlarged Iportion 21 interiorly thereof, with the groove 34 extending from the outer end of the sleeve 23 to the transverse shoulder 32.

The wires 11, 12 and 13 of the cable 14 secured to the plug part 21 are covered with layers 39, 4d and 41 (FIGS. 2 and 4) of an insulating material and with a cover 35 which is common to the three wires. The portion of the cover at the enr of cable is removed, and the insulating material 39 to 41 is removed from the end portions of the wires 11 to 13 to bare the end portions of the wires, The plug part 21 comprises three identical clamp members 36, 37 and 38 (FIG. 4) which are respectively secured to the bared ends of the wires 11 to 13. As shown in FIG. 6 which illustrates the clamp member 36 before connection with the wire 11, the clamp member 36 initially is generally tubular and includes a closed end 42 and an open end 43, the portion 45 of the clamp member 36 adjacent the open end 43 being enlarged relative to the portion 44 of the clamp 36 adjacent the closed end 42, thus forming a shoulder 46 at the juncture of the reduced portion 44 and the enlarged portion 45. The clamp members may be inexpensively manufactured because, with the foregoing construction, it will be seen that they may be made of sheet metal by drawing operations. While the wire 11 may be secured to the clamp member 36 by soldering, it is preferred that the wire 11 be secured to the clamp member 36 by inserting the bared end portion of the wire 11 into the open end 43 of the clamp member until the end of the wire reaches the shoulder 46, and then crimping or otherwise reducing the diameter of part of the length of the enlarged portion of the clamp member 36 to bring the enlarged portion 45 into tight mechanical and electrical engagement with the bared end portion of the wire 11. Thus the portion 45 of each clamp member is crimped onto the bared end portion of the wire for part of the length of the portion 4S as shown at 45a in FIG. 5, leaving an uncrimped part to receive the end of the wire.

The plug part 21 of the connector further comprises three contact members 47, 4S and 49, (FIG. 4) which are generally tubular and elongated. The reduced portions 44 of the three clamp members 36, 37 and 38 form prongs which are inserted into one end of the associated contact members 47, 48 and 49. The ends of the contact members 47 to 49 which receive the clamp members 36 to 38 may be flared outwardly, although this is not necessary. The prongs of the three clamp members iit into the ends of the three contact members with a snug or press lit in order to establish firm electrical connections between the clamp members and the contact members.

The three contact members 47, 48 and 49 are arranged in a triangular relation similar to that of the prongs 28 of the socket part of the connector, and the contact members 47 and 49 are held in this relation by a bushing 51 made of a somewhat yieldable insulating material such as rubber. The bushing 51 is generally circular in cross section and is adapted to be inserted into the socket portion 27 of the sleeve 23, as shown in FIG. 5. Longitudinally extending holes 52 are formed completely through the bushing 51, and the three contact members 47 to 49 are positioned in these holes 52. The contact members 47 to 49 are slightly shorter than the length of the holes 52, and the outer ends of the contact members are spaced inwardly from the end surface 53 of the bushing 5I. Since the holes 52 extend to the end surface 53 of the bushing, the prongs 28 of the socket part may be inserted through the openings of the holes 52 at the end face 53 and into the Contact members 47 to 49. To ensure firm electrical connections between the prongs 28 and the contact members 47 to 49, the internal diameters of the contact members 47 to 49 are preferably made substantially equal to or slightly less than the other diameters of the prongs 28, and the wall of each contact member 47 to 49 is longitudinally slit as at 54, the slits 54 permitting the contact members 47 to 49 to flex and expand slightly as the prongs 28 are inserted therein, such expansion of the contact members 47 to 49 resulting in a firm electrical connection between the prongs 28 and the contact members 47 to 49.

The bushing 51 extends from the face 53 rearwardly, or toward the left as seen in FIG. 4, to a point adjacent the upper ends of the contact members 47 to 49, and conical portions 50 are preferably formed on the bushing 51 around the contact members 47 to 49 as shown in FIG. 4.

The plug part 21 further comprises a one piece metal sleeve 57 surrounding the end portions of the wires 11 to 13 and the clamping members 36, 37 and 33, the sleeve 57 being coaxial with the bushing 51. The inner or right hand end of the sleeve 57 has a portion 58 of increased diameter which extends around the upper end portion (as seen in FIG. 4) of the bushing 51. The portion of the bushing 51, which is adjacent the sleeve 57, is enlarged to form a shoulder 59 limiting the extent to which the enlarged portion 58 of the sleeve 57 may be pushed down over the bushing 51. To provide a rigid backing for the bushing 51 and to hold the wires and the clamp members in place, the sleeve 57 is filled with a rigid potting compound 56, which extends into the enlarged portion 58.

In one method of assembling the plug part f the connector, the contact members 47 to 49 are positioned in the holes 52 of the bushing 51 and the clamp members 36 to 38 are secured to the bared end portions of the wires 11 to 13. After the nut and the sleeve 57 are slipped over the ends of the wires and on to the cable 14, the prongs of the three clamp members are inserted into the upper ends of the three contact members 47 to 49 and then the sleeve 57 is moved toward the bushing 51 and the increased diameter portion 58 of the sleeve 57 is pushed over the bush ing until it meets the shoulder 59. With the foregoing parts so assembled, the assembly is positioned with the cable 14 extending upwardly from the bushing 51 and the potting compound 56 in a liquid state is poured into the upper open end of the sleeve 57. The liquid ows around the wires 11 to 13 and the upper end portions of the three clamp members 36 to 39, and it completely fills the space within the sleeve 57. After the potting compound 56 has hardened, it holds the parts of the plug part in tightly assembled relation. The potting material, in completely filling the space within the sleeve 57 ts tightly on the conical portions 50 of the bushing 51 so that the length of the creepage path between any two of the clamping members 36 to 38 or the contact members 47 to 49 is materially increased over what it would be if the conical por- 4 tions were not present, thus decreasing the chance of fluid creepage.

Since it is important that each of the wires 11 to 13 be connected to va certain one of the wires 16 to 18, an orienting lug portion 61 (FIG. 4) is formed on the enlarged portion 58 of the sleeve 57. The rubber bushing 51 also has a radially extending lug 62 formed thereon a portion of which is received within the lug 61 of the sleeve 57. As the plug part is inserted into the socket part, the lugs 61 and 62 enter the groove 34, and the contact members 47 to 49 and the prongs 28 are arranged relative to the lugs 61 and 62 and the groove 34 such that the wires 11 to 13 and the wires 16 to 18 are properly interconnected.

The longitudinal dimensions of the plug part and the socket part are such that the lugs 61 and 62 must enter the groove 34 'before the contact members 52 of the plug part engage the prongs 28 of the socket part. To hold the plug part 21 in the socket part 22, the nut 25 is threaded into the threads 33 of the socket part 22, the nut bearing against the shoulder formed by the enlarged portion 58 of the sleeve 57.

The foregoing construction is advantageous for numerous reasons. The clalmp members 36 to 38 form excellent water barriers or blocks because of the closed ends 42 of the clamp members, and may be inexpensively manufactured because they do not require machining but may be drawn to form. lFurther, the tubular contact members 47 to 49 may also be inexpensively manufactured and they provide excellent electrical connections between the clamps 36 to 38 and the prongs 28. The construction is also advantageous in that the conical portions 50 on the rubber bushing 51 around the upper ends of the contact members 47 to 49 serve to increase the length of the creepage paths at the juncture between the bushing 51 and the potting compound 56. Still another advantage residing in this construction is that the orienting lug 61 is formed integrally with the sleeve 57, thereby eliminating the possi'bility that the lug 61 may become angularly displaced relative to the remainder of the sleeve 57 and the contact members 47 to 49. lIn addition, the integral construction of the sleeve 57 provides added space within the sleeve for the insulating potting compound 56 and the conductors and the sleeve 57, thereby reducing the possibility of a short circuit between the conductors or one of the conductors and the sleeve S7.

I claim:

1. A plug part for association with a socket part to form a sealed electrical connector and adapted to be secured to at least one wire, said plug part comprising at least one generally tubular clamp member which is closed at one end and open at its other end, said clamp member in said open end ybeing adapted to receive an end of said wire in electrical engagement therewith, at least one generally tubular contact member, said closed end of said clamp member being positioned in one end of said contact member and in press fit engagement therewith, and electrical insulating means around said members and supporting said members yfor telescopic engagement of the other end of said contact member with a prong of the socket part of said electrical connector, said insulating means comprising a relatively yieldable portion around said contact member and a relatively rigid portion around said clamp member, said yieldable and rigid portions abutting each other and the interface between said yield- -able and rigid portions 'being irregular around said contact member to increase the length of the creepage paths along said interface between said yieldable and rigid portions.

2. A plug part for association with a socket part to form a sealed electrical connector and adapted to be secured to at least one wire, said plug part comprising at least one generally tubular clamp member which is closed at one end and open at its other end, said clamp member in said open end being adapted to receive an end of said wire in electrical engagement therewith, at least one generally tubular contact member, said closed end of said clamp member being positioned in one end of said contact member and in press t engagement therewith, and electrical insulating means around said members and supporting 4said members for telescopic engagement of the other end of said contact member with a prong of the socket part of said electrical connector, said insulating means comprising a relatively yieldable member around said contact member and a relatively rigid member around a part of said clamp member, said yieldable and rigid members abutting each other and said yieldable member having a conical portion around said contact member and iitting tightly within the rigid member to increase the length of the creepage paths between the yieldable and rigid members from said clamp and contact members.

3. Apparatus as in claim 1, and further including a sleeve around said insulating means, said sleeve including a radially extending lug integrally formed thereon.

4. Apparatus as in claim 3, wherein said lug is hollow, and said insulating means includes an orienting lug portion which extends into said hollow lug of said sleeve.

5. A plug part for association with a socket part to form a `sealed electrical connector and adapted to be secured to a plurality of wires, said plug part comprising a plurality of generally tubular contact members, one end of each of said contact members being adapted to receive a prong of said socket part, a plurality of clamp members adapted to .be secured to the ends of said wires, each of said clamp members having a prong formed thereon which is inserted into the other end of the associated contact member, a relatively yieldable insulating member positioned around and supporting said contact members, a relatively rigid insulating member positioned around and supporting said clamp members, and a sleeve enclosing said rigid insulating member and partially enclosing said yieldable insulating member, said yieldable insulating member including a conical portion around each contact 'member and in tight engagement with said rigid insulating member.

6. A plug part for association with a socket part to form a sealed electrical connector and adapted to be secured to at least one wire, said plug part comprising a yieldable member made of an electrical insulating material, said members having a hole formed therethrough, a tubular contact member positioned in said hole, one end of said contact member being accessible for telescopic engagement with a prong of the socket part of said electrical connector, a generally tubular clamp member having one closed end and one open end, said open end being adapted to receive an end of said electrical wire and be electrically connected thereto, said closed end of said clamp member 'being positioned in the other end of said tubular connector member in press fit relation therewith, and relatively rigid electrical insulating means around said clamp member yand said end of said wire, said electrical insulating means yfurther being in iirm engagement with said yieldable member around said hole and thereby holding said clamp and contact ymembers in engagement and providing a rm backing for said yieldable member.

References Cited UNITED STATES PATENTS 2,296,766 9/1942 Bruno 339-177 2,761,110 8/1956 Edlen et al. 339-276 2,866,957 12/1958 Raypholtz 339-60 2,958,842 11/ 1960 Schaefer.

3,040,284 6/1962 Connell 339-61 3,309,647 3/1967 Von Holtz 339-276 FOREIGN PATENTS 746,000 3/ 1956 Great Britain.

MARVIN A. CHAMPION, Prmaly Examiner.

I. H. MCGLYNN, Assistant Examiner. 

1. A PLUG PART FOR ASSOCIATION WITH A SOCKET PART TO FORM A SEALED ELECTRCIAL CONNECTOR AND ADAPTED TO BE SECURED TO AT LEAST ONE WIRE, SAID PLUG PART COMPRISING AT LEAST ONE GENERALLY TUBULAR CLAMP MEMBER WHICH IS CLOSED AT ONE END AND OPEN AT ITS OTHER END, SAID CLAMP MEMBER IN SAID OPEN END BEING ADAPTED TO RECEIVE AN END OF SAID WIRE IN ELECTRICAL ENGAGEMENT THEREWITH, AT LEAST ONE GENERALLY TUBULAR CONTACT MEMBER, SAID CLOSED END OF SAID CLAMP MEMBER BEING POSITIONED IN ONE END OF SAID CONTACT MEMBER AND IN PRESS FIT ENGAGEMENT THEREWITH, AND ELECTRICAL INSULATING MEANS AROUND SAID MEMBERS AND SUPPORTING SAID MEMBERS FOR TELESCOPIC ENGAGEMENT OF THE OTHER END OF SAID CONTACT MEMBER WITH A PRONG OF THE SOCKET PART OF SAID ELECTRICAL CONNECTOR, SAID INSULATING MEANS COMPRISING A RELATIVELY YIELDABLE PORTION AROUND SAID CONTACT MEMBER AND A RELATIVELY RIGID PORTION AROUND 